The search for the source of antigen in a penicillin-sensitive patient can be a difficult and frustrating experience. The physician must be aware of diverse and unusual ways in which the drug can be introduced into the system. The milk of cattle treated with penicillin is now a well-known contact,1 as is poliomyelitis vaccine, but syringes contaminated by trace amount of the drug, penicillin-containing air, penicillin troches and ointment, and penicillin injected into cysts are other possible sources of exposure.2
Recently, I studied a 16-year-old white girl with acute urticaria resulting from the administration of penicillin in a paste used in endodontal repair of a tooth. At first I dismissed this site as a route of entry for the drug, since I thought that absorption into the systemic circulation after instillation into the dental root canal did not occur. However, further exploration revealed that systemic absorption from the
HURLEY HJ. A Dental Depot in Penicillin Hypersensitivity. Arch Dermatol. 1963;87(3):387. doi:10.1001/archderm.1963.01590150103020
Artificial Intelligence Resource Center
Customize your JAMA Network experience by selecting one or more topics from the list below.